Weight Loss Method Research Articles

Determination of weight loss methods and effects among wrestlers before an official championship

IntroductionIt is known that combat athletes frequently lose weight before a competition. This study aimed to determine the weight loss methods before an official championship and the effects of these weight loss methods on the performance of wrestlers.MethodThe sample of the study consisted of 350 competitive wrestlers. The “Athlete Weight Loss Methodology and Effects Scale” and personal information form were used as data collection tools in the study. In the data analysis, independent samples T-test, One-way ANOVA, and Pearson correlation analysis were used in addition to descriptive statistics.ResultsWrestlers generally reported dieting by restricting fatty (89.1%) and carbohydrate (83.4%) foods. It was observed that they preferred jogging with a raincoat (89.1%) and/or using the sauna (79.7%) as a weight loss method. Wrestlers also reported that they performed weight loss, although at a low level, by using ergogenic aids such as laxatives (31.7%) and/or diuretic pills (28.0%). They were observed to experience physiological effects such as muscle cramps (72.9%), injury (71.1%), and/or difficulty breathing (60.9%), as well as psychological effects such as feeling extremely tired (81.7%), stress (79.7%), decreased performance (78.6%) and/or extremely irritability (71.4%). It was determined that there was no difference between the weight loss methods and effects of the wrestlers according to their gender and wrestling style (p > 0.05). On the other hand, it was determined that the diet level of U20 wrestlers was higher than U17 (p < 0.05) and Senior wrestlers and that U17 and U20 wrestlers were exposed to higher levels of physiological and psychological effects than Senior wrestlers (p < 0.05).ConclusionIt was determined that wrestlers preferred methods such as restricting food and fluids, using a sauna, and jogging with a raincoat to lose weight. It is necessary to prevent young wrestlers from losing weight before the competition. Thus, it is possible to prevent wrestlers in their development period (U17 and U20) from being exposed to physiological and psychological effects caused by losing weight.

Food insecurity and weight-loss efforts among a nationally representative sample of US adults with higher weight.

The objective of this study was to examine the prevalence of food insecurity among a nationally representative sample of US adults who were attempting weight loss, as well as the associations of food insecurity with weight-loss strategies. This study included adults with BMI ≥ 25.0 kg/m2 who were intentionally trying to lose weight within the past year from the 2017 to March 2020 data cycle of the National Health and Nutrition Examination Study. Participants were categorized as either food insecure or food secure (US Food Security Survey Module), and their use of weight-loss strategies was compared using unadjusted logistic regression models and models adjusted for sociodemographics. Nearly one-quarter (22.96%, n = 582) of participants were food insecure. In unadjusted models, participants with food insecurity were more likely to use unhealthy weight-loss methods (e.g., skipping meals, taking laxatives or vomiting) and less likely to use healthy methods (e.g., exercising, joining a weight-loss program; p < 0.05). In adjusted models, participants with food insecurity were less likely to join a weight-loss program and eat less sugar, candy, and sweets. Food insecurity is common among US adults with higher weight who are trying to lose weight, and individuals with food insecurity are less likely to use healthy weight-loss strategies.

Understanding the Relationship between the Ketogenic Diet and the Heart: A Novel Therapeutic Potential for Cardiovascular Health.

Obesity and cardiovascular diseases are major health problems worldwide, and weight loss is used as a treatment strategy to enhance various aspects. While there are many weight loss methods, one of the most effective is through a dietary approach. The ketogenic diet (KD), which is characterized by low carbohydrates and high levels of fat and/or protein, is used in obese patients as it is a promising treatment option for weight loss as well as for controlling the risk factors for cardiovascular diseases, as seen in its effects on cardio-metabolic outcomes, particularly in obesity, heart failure, and hypertension. In this review, we summarize the clinical evidence of the efficacy and safety of the KD in controlling risk factors for cardiovascular diseases and discuss the possible mechanisms of action based on recent evidence in understanding the influence of the KD at the cellular and molecular levels.

Weight loss and electrochemical measurements of aluminum corrosion in diesel fuel and biodiesel prepared via transesterification of waste cooking oil

Recent studies have found potentials in the utilization of biodiesel from renewable energy sources to tackle environmental pollution associated with the release of exhausts from fossil diesel fuel engines. However, it's imperative to investigate the corrosion rate and nature of the engine components fuelled with the biodiesel. This study examines the corrosion rate and nature of aluminum coupon (AC) in fossil diesel fuel (DF) and biodiesel produced from waste cooking oil via transesterification reaction (WCOB) using weight loss and electrochemical measurements. Taguchi Orthogonal Array was used to study the influence of temperature, immersion time, agitation and WCOD/DF volume. Weight loss method revealed highest corrosion rates to be 0.0052 mm y−1 and 0.0381 mm y−1 for AC in DF and WCOB respectively. Corrosion rate increased with increase in immersion time and temperature. A shift in the corrosion potential from -0.192 V to -0.574 V; and -0.178 V to -0.516 V was revealed by potentiodynamic polarization curve for AC in WCOB and DF respectively. Nyquist plots exhibited relatively perfect semicircles of different diameters and similar shape. The developed mathematical models were effective for corrosion rate prediction. Minimum corrosion rates of 1.222 × 10−3 mm y−1 and 1.822 × 10−3 mm y−1 for AC in DF and WCOB are respectively feasible at optimum point. Presence of carbon and oxygen on AC surface; pits formation; and loss of Al ion into WCOB and DF after corrosion were noticed. In conclusion, the corrosion rate of AC in WCOB was higher than the DF counterpart.

Maladaptive eating habits in judo athletes and psychological side effects: Case studies

Originating in 19th-century Japan, judo blends traditional martial arts with modern educational principles. As a martial art rooted in the Budo tradition, it embodies a philosophy focused on the harmony of mind and body. In the West, however, the discipline evolved with an emphasis on competition and athleticism, which has led to increased competitive pressures among athletes. We report here the case studies of two Italian judokas who retired due to the development of unhealthy eating habits, extreme exercise and other unwanted psychological distress. It will be argued that the prevalent practice of weight cutting in combat sports poses substantial physical and psychological risks, particularly for young athletes. Despite regulatory efforts to mitigate extreme weight loss methods, there remains a critical need for improved education on safe practices. It sheds light on the complex interplay between athletic success, physical and mental health, and cultural perceptions of Judo in contemporary society.

Novel eco-friendly quinolinone derivative as a water-soluble corrosion inhibitor for low carbon steel: Synthesis, inhibitive efficacy, and DFT analysis

A novel and rapid synthetic route for producing 4-imino-3-(2-phenylhydrazono)-3,4-dihydroquinolin-2(1H)-one (IQ) from 3-(2-phenylhydrazono)quinoline-2,4(1H,3H)‑dione 1 is introduced. The inhibitory effectiveness of IQ in mitigating the corrosion of low carbon steel (LCS) in acidic environments was evaluated using weight loss (Wt-L) and electrochemical methods, such as potentiodynamic polarization (Pd-P) and electrochemical impedance spectroscopy (EIS). The optimum concentration of IQ was determined to be 30×10−3 Mm, at which it exhibited the highest inhibition efficiency of approximately 93.2 %. The nature of IQ as a mixed-type inhibitor was demonstrated by its ability to inhibit both anodic and cathodic reactions, primarily acting as an anodic inhibitor.The adsorption of IQ onto the LCS surface followed the Langmuir adsorption model, indicating a monolayer adsorption mechanism. Moreover, EIS findings suggest that IQ forms a protective layer on the LCS surface at the metal/electrolyte interface, preventing its dissolution in the acidic medium. Further analysis of the corrosive solution containing IQ after two days of LCS immersion showed the formation of Fe-IQ complex, confirmed by ultraviolet/visible spectroscopy. Using atomic force microscopy (AFM), we confirmed that a protective layer of IQ forms on the surface of LCS. Additionally, in silico studies of IQ revealed the active sites responsible for its interaction with the LCS surface under acidic conditions. These findings underscore the potential of IQ as an effective corrosion inhibitor for LCS in acidic environments, providing significant protection by forming a stable, protective film on the metal surface.

Eco-friendly impact of a novel green Melilotus officinalis extract as a sustainable inhibitor to reduce acid corrosion of copper.

In this study, we deployed green Melilotus officinalis extract (MOE) as a corrosion inhibitor for copper. The anticorrosion properties of MOE for Cu in 1 M HNO3 were investigated by various experimental and numerical techniques, including potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS), and a weight loss (WL) method at different temperatures. Additionally, scanning electron microscopy (SEM) coupled with energy-dispersive X-ray analysis (EDX) and atomic force microscopy (AFM) were utilized to examine the surface morphology of Cu with and without the extract. By contrasting the inhibition effectiveness with and without the extract, the inhibition efficiency (% IE) was observed. The WL method revealed that 300 ppm of the extract had an IE of 93.8% for Cu immersed in one molar HNO3 solution. The MOE was classified as a mixed type according to the PDP study since it delayed both cathodic and anodic processes, with a cathodic predominance. At 25-45 °C, MOE's free adsorption energies were 23.1-21.5 kJ mol-1, showing that mixed-type adsorption occurred on the Cu surface. Additionally, the Langmuir adsorption isotherm and the adsorption data from the WL tests of MOE showed a good match. The extract could adsorb spontaneously onto the metal surface, according to the thermodynamic conditions. Analysis of the corrosion product using different techniques revealed that a protective layer had formed on the metal's surface. Hence, MOE had a good corrosive inhibitive effect on Cu in HNO3 solution. It turned out that all the methods used gave consistent results.

Rare Earth 4‐Hydroxyphenylacetate Complexes: Synthesis, Structural Characterization, and Corrosion Inhibition Properties#

Four different structural types of rare earth aqua 4‐hydroxyphenylacetate complexes {[Ce(L)3(H2O)2]⋅H2O}n (a), {[RE2(L)6(H2O)]⋅4H2O]}n (RE = Nd (b), Gd (c)), {[RE2(L)6(H2O)]⋅3H2O]}n (RE = Dy (d), Y (e)), {[RE2(L)6(H2O)]⋅5H2O]}n (RE = Er (f), Yb (g)), (L = 4‐hydroxyphenylacetate) have been synthesized by the metathesis reactions of corresponding rare earth metals chlorides or nitrates and sodium 4‐hydroxyphenylacetate (NaL). All compounds were obtained as 1‐D polymeric structures, with a common carboxylate coordination mode of chelating bridging. The structure of a differs in being a monometallic repeating unit and having two coordinated waters whilst the others have binuclear repeating units that resulted from the alternating coordination of one water molecule along the chain. Corrosion tests by the weight loss method and potentiodynamic polarisation tests revealed that {[Gd2(L)6(H2O)]⋅4H2O}n has the best corrosion inhibition properties for mild steel in 0.01 M NaCl. Furthermore, all a‐g complexes are more effective corrosion inhibitors than both the aqua and 2,2’‐bipyridine (bpy) complexes of unsubstituted phenylacetate indicating that 4‐OH substitution of phenylacetate enhances anti‐corrosion properties.

Corrosion inhibition performance of expired amlodipine on cupronickel alloy in a neutral chloride environment: electrochemical and surface analysis

Purpose The corrosion of cupronickel and copper alloys in marine and chloride environments presents significant challenges in the chemical and petrochemical industries. This paper aims to investigate the corrosion inhibition of cupronickel alloy (Cu-10Ni) in a sodium chloride medium using expired amlodipine as a corrosion inhibitor. The use of this drug in its expired form could reduce the costs of corrosion and help mitigate the accumulation of pharmaceutical waste. Design/methodology/approach The inhibitory action was evaluated using a weight loss method, potentiodynamic polarization, electrochemical impedance spectroscopy measurements, scanning electron microscopy (SEM) and atomic force microscopy (AFM). The effect of temperature on the inhibition performance was also studied. Findings The results of these experiments demonstrated that the drug amlodipine effectively inhibited the corrosion of cupronickel alloy in chloride solutions. The corrosion rate of cupronickel was found to decrease with increasing inhibitor concentration and to increase with rising temperature. A maximum inhibition efficiency of 91.92 was achieved with an inhibitor concentration of 0.025 g/L at 298 K. Adsorption of the inhibitor followed the Langmuir adsorption isotherm. Polarization studies indicated that the expired drug acted as a mixed inhibitor. SEM and AFM analyses confirmed that the surface morphology of cupronickel specimens was significantly improved in the presence of the inhibitor. Practical implications Amlodipine can be conveniently used to mitigate problems with the corrosion of copper alloys in chloride environments. Originality/value Amlodipine is evaluated as a novel and effective corrosion inhibitor for cupronickel alloy in neutral chloride environments.

Prevalence and patterns of pre-competition weight loss practices in Chinese Amateur boxers

This study investigated the weight loss (WL) practices of Chinese amateur boxers using the Rapid Weight Loss Questionnaire (RWLQ). A total of 701 (563 males, 138 females) boxers participated in the study and were categorized by sex, age group, and competitive level. Sixty-seven percent of boxers purposefully engaged in WL practices before competition. The average habitual WL was 6.0% (5.8% for juniors and 6.3% for seniors) of body mass (BM), with the average highest WL was 9.5% (9.1% for juniors and 10.1% for seniors) of BM. Most participants (69% for juniors and 84% for seniors) allocated 15+ days for WL before competition. No significant differences in habitual WL%, highest WL%, and rapid weight loss score (RWLS) were found between age groups or competitive levels (all p &gt; 0.05). However, males’ highest WL% and RWLS were significantly higher than females (p &lt; 0.001, p = 0.002, respectively). International boxers began WL later than local boxers (15.5 vs. 14.3 years, p = 0.012). National boxers began WL later than provincial and local boxers (15.6 vs. 14.8 years, p &lt; 0.001; 15.6 vs. 14.3 years, p &lt; 0.001). Increased exercise and training in plastic suits were the most frequently used WL methods. Coaches were identified as the most influential person concerning boxer's WL practices, surpassing doctors or nutritionists. This study found that some WL practices among Chinese boxers differ from those in other sports and countries. Although the prevalence of WL among junior boxers was relatively low, the magnitude of WL was high, warranting more attention in both academic and practical fields.

Evaluation of the Effect of Static and Flowing Conditions on the Corrosion Behavior of the Hull of Marine Ships

Marine ship hulls' corrosion resistance behavior under static and flowing conditions was investigated. The metal of the hull panels of marine ships was chemically and mechanically examined and analyzed, revealing that carbon steel type DIN 1.0501 C35 is employed in constructing the hull of ships in the port of Basrah in Iraq. A corrosion resistance test for this metal was carried out in laboratory-prepared seawater under static and flowing conditions at a flow rate of 1500 liter/hour and various immersion times (12, 24, 48, 120, 168, 336) hours. The temperature was kept constant at 30°C, and a fixed salt concentration of (3.5% sodium chloride). The corrosion rate of C35 carbon steel was calculated using the weight loss method is an effective method for calculating the corrosion rate of carbon steel. The samples were examined using a scanning electron microscope (SEM) for corrosion analysis. Conclusions from this research indicate that an increase in the flow rate resulted in an elevation of the corrosion rate, doubling the corrosion rate compared to samples under static conditions. The corrosion rate exhibited a significant increase during the first 24 hours, followed by a gradual decrease with increasing immersion time. The corrosion rate increased by 682.9%. The speed of corrosion was fast initially, but the weight loss slowed after 24 hours of immersion. A scanning electron microscope (SEM) examination revealed that the flow environment was aggressive for carbon steel. It was much more severe, and the pits and grooves were more significant than the static condition.

Changes in the corrosion rate and microstructure of nickel titanium wire in pandan leaves extract

OBJECTIVE: This study aimed at determining the effect of pH changes on nickel titanium wire seen based on the corrosion rate and surface roughness of the wire after immersion in pandan leaves extract. MATERIAL AND METHODS: The sample used nickel titanium wire of 0.016 inches diameter and 5 cm length and consists of five treatment groups: control group, 0.2% chlorhexidine, and 1000 ppm, 2000 ppm, and 4000 ppm pandan leaves extract. The solutions were put into an incubator for 7, 14, and 21 days at 37 °C and removed according to the sample immersion time. The corrosion rate was determined using the weight-loss method, and microstructure roughness was analyzed using a scanning electron microscope. RESULTS: Kruskal–Wallis test showed that there was a significant difference in corrosion rate of orthodontic wires of nickel titanium after control submersion, 0.2% chlorhexidine, and pandan leaves extract on 7, 14, and 21 days (P ≤ 0.05), and pandan leaves extract submersion shows that the surface structure is not as bad as artificial saliva and 0.2% chlorhexidine. CONCLUSIONS: Pandan leaves extract could inhibit the corrosion rate of nickel titanium orthodontic wire, which might be due to tannin content as an active antioxidant.

Effects of water content on the corrosion behavior of NiCu low alloy steel embedded in compacted GMZ bentonite

Buffer material and metal disposal containers are the key engineering barriers in the geological disposal of high-level radioactive waste. The durability of disposal containers largely depends on the water content in buffer material. This work focused on investigating the corrosion evolution of NiCu low alloy steel in compacted GMZ bentonite with different water contents for 270 d by using weight loss, electrochemical measurements, and various methods for analyzing corrosion products. As the water content increased from 13% to 20%, the water in the bentonite transformed from an unsaturated to a critical saturated state, and the corrosion rate of NiCu steel clearly increased. In these two systems, the oxygen could migrate to the thin liquid film on the steel surface through the air pores in the bentonite in the gas phase and undergo cathodic reduction. Meanwhile, it oxidized the ferrous hydrolysis products into ferric corrosion products and formed a rust layer, which could block the diffusion of oxygen. At that moment, the cathodic process of NiCu steel corrosion changed to rust reduction. When the water content continually increased to 30% and 40%, the compacted bentonite was in a saturation state, and the corrosion rate of NiCu steel was significantly decreased. This was because most pores among the bentonite particles were occupied by a large amount of free water, which hindered the diffusion of oxygen and inhibited its cathodic reduction. Furthermore, it restrained the oxidation of ferrous corrosion products, which greatly weakened the cathodic depolarization of rust, leading to the cathodic process being dominated by the hydrogen evolution reaction.

Corrosion Inhibition and Adsorption Behaviour of Centrosema pubescens Leaf Extract for Copper in HCl Solution

Study’s Excerpt In this study, Centrosema pubescens leaf extract (CPE) has been confirmed as eco-friendly and efficient green inhibitor for copper corrosion in hydrochloric acid. Detailed thermodynamic analysis, revealed that CPE adsorption follows a Freundlich isotherm model. SEM-EDX and FTIR characterizations confirmed the formation of a protective layer confirming the potentials of the plant extracts in sustainable corrosion prevention. Full Abstract The anti-corrosion behaviour of Centrosema pubescens leaf extract (CPE) on copper in 1.5 M hydrochloric acid was investigated using weight loss method at different temperatures, followed with scanning electron microscopy (SEM) surface characterization connected with energy dispersive X-ray spectroscopy (EDX). The Fourier transform infrared spectrum of CPE was obtained. CPE inhibition effectiveness depends on the temperature and its concentration. CPE restrains the copper corrosion with 94.26 % inhibition efficiency at 1.0 g/L of CPE and at 303 K. For the CPE-inhibited system, a higher activation energy (Ea) value (range of 31.09 to 38.70 kJmol-1) compared to 20.34 kJmol-1 of the blank solution was obtained. The reaction process is spontaneous and endo thermic, as indicated by the ΔH, ΔS and ΔG values calculated. CPE adsorption behaviour fitted best into Freundlich isotherm.

The comparison of eight different common in vitro and ex vivo environments with in vivo conditions applying model collagen samples: Correlation possibilities and their limits

New biomaterials are routinely evaluated for their degradation behaviour in the real body environment. Following the 3R strategy, in vitro simulated body conditions are often preferred. No studies that simultaneously compare such conditions with the real body environment have been conducted to date. Model porous collagen scaffolds were exposed for 21 days to eight different environments: simple salt-based and enzymatic media, human blood plasma, cell culture media with and without human fibroblasts and ex vivo model cortical bone, and subsequently compared with an in vivo environment represented by a pig peritoneum. The mechanical properties of the scaffolds were then determined via uniaxial compression testing, and the structural properties via the micro-CT, weight loss, infrared spectroscopy, X-ray diffraction and histological methods. Interestingly, the various analysed simulated body conditions caused differing alterations in the collagen scaffold characteristics when compared with the real body environment. The mechanical properties were similar during the first 7 days of incubation but diverged after 14 and 21 days. The structural properties varied significantly after just 7 days of incubation. The histological evaluation of the scaffolds exposed to the cellular, ex vivo and in vivo conditions revealed the poor ability of cells to completely populate the scaffolds, accompanied by the massive ingrowth of connective tissue into the in vivo exposed scaffolds, which resulted in their variable global behaviour. In conclusion, the value of in vitro simulated body environments lies in their screening capacity and feasibility; however, direct extrapolation to real body conditions needs to be verified going forward.

Synthesis and evaluation of an environmentally friendly phosphorus-free and nitrogen-free polymer as a scale and corrosion inhibitor

Polyepoxysuccinic acid (PESA) was modified by glycidyl (Gly) to obtain a phosphate-free and nitrogen-free polymer (Gly-PESA), and its scale and corrosion inhibition properties were studied.The effects of Gly-PESA concentration, calcium ion concentration and temperature to scale inhibition performance were studied by static scale inhibition method. The corrosion inhibition performance of Gly-PESA was studied by static weight-loss method. The morphology and structure of calcium scale and steel surface were characterized by spectroscopic and microscopic methods. The scale inhibition efficiency of Gly-PESA for CaCO3 and CaSO4 was 98.06% and 92.6%, respectively. Under the same experimental conditions, the scale inhibition effect of Gly-PESA was obviously better than that of PESA. Gly-PESA could effectively inhibit the growth of CaCO3 and CaSO4 crystals and cause their crystal lattice distortion or crystal dispersion. The corrosion inhibition efficiency of Gly-PESA for carbon steel was 78.17%. The adsorption of Gly-PESA on the surface of the steel test piece followed Langmuir adsorption isotherm, and formed a protective film, which increased the corrosion resistance of the steel test piece, thus effectively protecting the steel test piece. Therefore, Gly-PESA was a green scale and corrosion inhibitor, which solved the problem of environmental pollution.

Effect of Al content on mechanical properties and corrosion performance of novel Fe-Cr-Al alloy steels in a CO2-O2 coexistence environment

The present study involved preparing five novel Fe-Cr-Al alloy steels with varying Al content based on commercially available 3Cr steel. The effect of Al content on the mechanical properties and corrosion performance in a CO2-O2 coexistence environment was investigated in novel Fe-3Cr-(0–2.5)Al alloy steels, and the microhardness, impact, and tensile properties were measured and compared. The corrosion rate, corrosion product film, and corrosion mechanism were studied using a weight-loss method, microscopic characterization, and electrochemical tests. The results showed that the tensile and impact properties of Fe-Cr-Al alloy steels exhibited a decreasing trend with increasing Al content. No localized corrosion was observed at an Al content of 2 wt%, attributed to the formation of a dense amorphous corrosion product film on the material surface and pre-passivation. Among the alloy steels examined in this study, the 3Cr2Al alloy steel exhibited the most optimal balance between mechanical properties and corrosion resistance.

The effects of ECAP, Mn and Ca elements on the microstructure and corrosion properties of magnesium alloys were investigated

In this study, through reasonable composition design, three elements of Zn, Mn and Ca, which are harmless to human body, were selected for alloying magnesium. The effects of ECAP treatment on the microstructure and corrosion properties of Mg-4Zn-1Mn-0Ca, Mg-4Zn-1Mn-0.2Ca and Mg-4Zn-0Mn-0.2Ca alloys were studied. The corrosion mechanism of Mg-Zn-Mn-Ca alloys with different components in Simulated. Body fluid (SBF) was analyzed by weight loss method and electrochemical test. The grains and the second phase were refined by Equal Angular Channel Pressing (ECAP). It was found that after 8 ECAP deformations, the microstructure of the alloy was refined and more uniform than that of the extruded alloy. The corrosion resistance of the Mg-Zn-Mn-Ca alloy after ECAP deformation in simulated body fluids was studied by electrochemical testing techniques, immersion experiments and observation of the microstructure and morphology of corrosion products. The relationship between microstructure characteristics, the behavior of the magnesium metal matrix and the properties of corrosion products was revealed. The results show that the microstructure of the alloy is refined and the corrosion resistance is improved with the increase in extrusion passes in the SBF solution. The corrosion resistance of magnesium alloy after 8 ECAP deformation is the best, showing small Icorr and large Rt. With the extension of the soaking time, the surface of the alloy will form a passivation film, which will protect the matrix and avoid further corrosion of the alloy. It is found that in SBF, the corrosion of the alloy surface is mainly pitting, which indicates that Ca2+, HCO3- and HPO42- in SBF can reduce the corrosion rate of magnesium alloy.

Comparison of crevice corrosion of P110S and HP-13Cr in extremely aggressive environment containing CO2 and H2S

The crevice corrosion of P110S steel and HP-13Cr stainless steel (SS) in different simulated oil and gas environments was investigated using a modified crevice corrosion apparatus, surface analysis techniques and weight-loss method. In addition, the corrosion behavior of the two different pipeline steels was explained using the dissolution-ionization-diffusion-deposition (DIDD) model in combination with passive dissolution model and metastable pitting model. The results indicate that there is no crevice corrosion phenomenon in P110S steel, and there is no coupling effect between H2S and CO2. P110S steel experienced crevice corrosion at the beginning of the experiment, but later the corrosion products inside the crevice began to thicken, and the states inside and outside the crevice gradually converged. Moreover, significant crevice corrosion was observed for HP-13Cr SS, and CO2 and H2S had a coupling effect. The crevice corrosion phenomenon can be explained by metastable pitting model.

Exploring the Experimental and Theoretical Studies and Inhibition Mechanism of Passiflora Incarnata Extract as a Novel Green Inhibitor for API 5CT N80 in an Aggressive Environment.

Corrosion is a crucial problem worldwide that heavily affects natural and industrial environments and can cause machinery breakdown and deterioration of construction assemblies, thus threatening the lives of humans and accelerating the consumption of natural metal reservoirs. In this study, we deployed passiflora incarnata extract (PIE) as an eco-friendly green inhibitor to prevent API 5CT N80 (CS-N80) corrosion in 1 M HCl. The chromatograms of the gas chromatography-mass spectroscopy analysis of PIE have identified 25 compounds. The weight loss method reveals that 150 ppm of the extract offers 90.4% inhibition efficiency (IE) to CS-N80 immersed in 1 M HCl solution at 25 °C. However, at higher temperatures (45 °C), % IE increases and reaches 92.1%. The electrochemical characterization of the adsorbed layer on CS-N80 was tested by utilizing electrochemical methods (electrochemical impedance spectroscopy and polarization) in 1 M HCl. Polarization diagrams displayed that PIE is a mixed-type inhibitor that retards CS-N80 corrosion. Temkin adsorption isotherm is the best fit for adsorbed PIE on the CS-N80 surface. IE was improved by raising the temperature (chemical adsorption). Examining the morphology of CS-N80 sheets through scanning electron microscopy, energy-dispersive X-ray, X-ray photoelectron spectroscopy, and Fourier transform infrared analysis furnishes valuable insights into their surface characteristics. The results of a quantum chemical computation show that the three PIE components have strong anticorrosion properties. According to findings from molecular dynamics simulations, the three PIE components can have a high binding energy and can be adsorbed in a parallel manner at the Fe(110) surface. All tests have shown that the PIE composite conversion adsorbed with a self-healing property and lower corrosion current density was precipitated on the steel surface.